Double acting switch



July 17, 1956 w. P. BIRKEMEu-:R

DOUBLE 'CTING SWITCH Filed Sept. 26 1952 IN V EN TOR. [Val/4M /Z/Ammuf/f@ by 4 y BY nited States Patent DOUBLE ACTING SWITCH William P.Birkemeier, Cedar Rapids, Iowa, assigner to Collins Radio Company, CedarRapids, Iowa, a corporation of Iowa Application September 26, 1952,Serial No. 311,629

3 Claims. (c1. 20o-67)v This invention relates in general to switches,and in particular to a double-acting switch.

It is an object of this invention to provide a doubleacting single poledouble-throw switch.

Another object of this invention is to provide an improved switch whichsuccessively moves from a first to a second position and returns uponsuccessive motion of an actuating button.

A feature of this invention is found in the provision for a containerwherein a generally S-shaped spring is mounted with the center pivotedand an actuating Y- shaped push button movable transversely of saidspring.

Further features, objects and advantages of the invention will becomeapparent from the following description and claims, when read in view ofthe drawings, in which:

Figure l is an isometric view of this invention,

Figure 2 is a sectional view of the invention,

Figure 3 is a sectional View taken on line 3 3 of Figure 2, and

Figure 4 illustrates the electrical equivalent of the switch.

Figure l illustrates a container member, designated generally as 10,which has three contacts 11, 12 and 13, respectively, extendingtherefrom and a push button 14 extending through the top cover 15.

As best shown in the sectional view of Figure 2, mounted within thecontainer member 10, is an S- shaped spring member 16 which has its ends17 and 19 mounted in slots 20a and 20b formed in the end walls 18 and21. A pivot pin 22 is mounted in the center of the container and isattached to the liexible member 16 at its center.

A pair of brackets 23 and 24 support the pivot pin 22.

A downwardly extending guide 25 is attached to the top of the container10 and the push button 14 is received therein. A generally bifurcatedyoke 26 is attached to the push button 14 and extends into the coninesof the container 10. The legs 27 and 28, respectively, of the yoke 26are alternately engageable with the spring 16.

A button contact 29 is mounted in the end wall 30 of the containermember and is engageable with one side of the spring 16. A second buttoncontact 31 is mounted in the end wall 30 and is engageable with theother side of the spring member 16.

In operation when the push button 14 is depressed, the leg 27 or 28which is in contact with the spring 16 pushes the particular side downso that it goes from a rst to a second stable position. The rst stableposition is shown in solid line in Figure 2 and the other stablecondition is shown in dotted line.

Let it be assumed that the switch is initially in the position shown insolid lines in Figure 2 and that it is required to reposition springmember 16 to the reverse S-shaped position shown in dotted lines.

In the iirst instance, S-shaped member 16 is formed Patented, July 17,1956 with a high curved portion on the left side in Figure 2 and a lowcurved portion on the right side.

If yoke 26 is momentarily depressed, finger 27 engages the high side ofspring member 16 and depresses it until the high portion adjacent thecenter is bent oppositely from the remainder of the high portion.

After the high portion is indented sutlciently and before the lowportion on the right is engaged by the other finger 28, a wave actionoccurs along the length of spring member 16 to reverse its position tothat shown in dotted lines in Figure 2.

The reversal of member 16 is accompanied by a change of position of itsends. End 17, which was previously at the lower edge of notch 20a, lisnow at the upper edge; while end 19, which was previously at the upperedge of notch 20h, is now at the lower edge. Hence, when spring 16 wasactivated, its ends 17 and 19 slide to the opposite edges of theirnotches.

When considered in an over-all manner, yoke 26 is actuatedperpendicularly to spring 16. But this 'is not the case when consideredduring an instant of operation. For example, in the solid representationof member 16 in Figure 2, a straight line drawn from end 17 to end 19will not be perpendicular to the direction of movement ofV yoke 26 butwill be slightly oblique. Similarly, in the dotted representation ofmember 16 in Figure 2, a line drawn between the ends or" spring 16 willnot be perpendicular t o the movement of yoke 26 but will be disposedobliquely. and oppositely from the rst drawn line. As indicated above,kit is only the over-all average position of the lines which will beperpendicular to the movement of yoke 26.

Consequently, the movement of ends 17 and 19 in notches 20a and 2Gbshifts the point of unbalance for spring member 16 so that it lendsitself to a condition of instability after a short amount of downwardmovement by the equal length fingers of yoke 26. The condition ofinstability is favorable to the yoke finger which engages the high sideof member 16. In one sense, yoke fingers 27 and 28 do not appear withequal length to spring member 16 because before actuation the linebetween the yoke ends is not perpendicular to the movement of thelingers 27 and 28. Hence, each finger is more effective than the other,depending on the initial position of spring member 16.

Once the button 14 is depressed, the switch remains in that positionuntil the button is released and pressed again. When this occurs theside opposite the rst side will be engaged by the yoke 26 and the switchwill move to the second stable condition.

It is a trigger switch similar in some respects to an electronic triggercircuit.

Figure 4 illustrates the electrical equivalent of the switch.

It is seen that this switch provides a single pole doublethrow switch.

Although the invention has been described with respect to a particularembodiment thereof, it is not to be so limited as changes andmodifications may be made therein which are within the full intendedscope of the invention as dened by the appended claims.

I claim:

1. A double-acting switch comprising a container member, a pivotingbracket mounted within said container member, a ilexible conductingmember of spring material having a length greater than said containerand mounted within said container and pivotally and slideably supportednear its center by said bracket, said exible conducting member formed ina reversible S-shape with an upward side and a downward side while in asteady-state position, slots formed in the ends of said container andreceiving the ends of said exible member,

at least one of said slots formed with a smooth surface substantiallylonger than the thickness of said exible member for relative slidingmovement, a bifurcated yoke slideably supported by said container memberwherein its sliding direction is generally transverse to said llexiblemember, said yoke having a pair of legs extending symmetrically onopposite sides of said bracket, said yoke being spring biased away fromsaid ilexible conducting member, one of said yoke legs capable ofengaging the upward side of said flexible member when said yoke ismomentarily depressed, and electrical contacts mounted on opposite sidesof said container and engageable with opposite sides of said exiblemember.

2. A double-acting switch comprising a container member, opposite sidesof said container member formed internally with rectangular notches, aspring member formed of flat material and having opposite ends receivedin said rectangular notches, the ends of said spring member slideable insaid notches in a direction generally transverse to the mean plane ofsaid spring member, said spring member longer than the distance betweensaid notches and formed generally in an S-shape, means for slideably andpivotally supporting the center portion of said spring member, abifurcated member supported by said container and slideable in adirection transverse to the mean plane of said spring member, the endsof said bifurcated member extended respectively toward opposite sides ofsaid spring member, said bifurcated member spring biased with its endsnormally out of engagement with said spring member, a respective end ofsaid bifurcated member engaging one side of said spring member when saidbifurcated member is depressed, the sides of said spring member reversedin position after actuation by a respective end of said bifurcatedmember,

and electrical contacts disposed on opposite sides of said spring memberand container for successive engagement when said bifurcated member isactuated.

3. An actuating member for a switch having a container comprising aspring member formed of at and resilient material, said container formedinternally on one side with a rectangular notch greater than the widthof said spring member and several times thicker, the opposite internalwall of said container formed with a second notch, opposite ends of thespring member received respectively in said notches, said spring memberbeing longer than the distance between said notches and held generallyin an S-shape with upward and downward sides, means secured to saidcontainer supporting the center portion of said spring member in aslideable and pivotal manner, a bifurcated member having oppositelyextending legs and slideably supported by said container transverse tothe mean plane of said spring member, one leg of said bifurcated memberengageable with the upward side of said spring member when saidbifurcated member is momentarily depressed, whereby the S-shaped springmember reverses its upward and downward sides after the momentaryengagement with said bifurcated member,

References Cited in the le of this patent UNITED STATES PATENTS2,113,227 Bokeeno Apr. 5, 1938 2,374,435 Jordan Apr. 24, 1945 2,395,698Tiffany Feb. 26, 1946 FOREIGN PATENTS 956,154 France July 18, 1949

